The present invention relates to agricultural seeding machines, and, more particularly, to seed metering systems used to meter (e.g., singulate) seeds.
An agricultural seeding machine such as a row crop planter or grain drill places seeds at a desired depth within a plurality of parallel seed trenches formed in soil. In the case of a row crop planter, a plurality row crop units are typically ground driven using wheels, shafts, sprockets, transfer cases, chains and the like. Each row crop unit has a frame which is moveably coupled with a tool bar. The frame may carry a main seed hopper, herbicide hopper and insecticide hopper. If a granular herbicide and insecticide are used, the metering mechanisms associated with dispensing the granular product into the seed trench are relatively simple. On the other hand, the mechanisms necessary to properly meter the seeds, dispense the seeds at a predetermined rate and place the seeds at predetermined relative locations within the seed trench are relatively complicated.
The mechanisms associated with metering and placing the seeds generally can be divided into a seed metering system and a seed placement system which are in communication with each other. The seed metering system receives the seeds in a bulk manner from the seed hopper carried by the frame. Different types of seed metering systems may be used such as seed plates, finger plates, and seed discs. In the case of a seed disc metering system, a seed disc is formed with a plurality of seed cells spaced about the periphery thereof. Seeds are moved into the seed cells, with one or more seeds in each seed cell depending upon the size and configuration of the seed cell. A vacuum or positive pressure air may be used in conjunction with the seed disc to assist in movement of the seeds into the seed cells. The seeds are metered (e.g., singulated) and discharged at a predetermined rate to the seed placement system.
The seed placement system may be categorized as a gravity drop system or a power drop system. In the case of a gravity drop system, a seed tube has an inlet end which is positioned below the seed metering system. The metered seeds from the seed metering system merely drop into the seed tube and fall via gravitational force from a discharge end thereof into the seed trench.
A seed placement system of the power drop variety generally can be classified as a seed conveyor belt drop, rotary valve drop, chain drop or air drop. These types of seed placement systems provide more consistent placement of the seeds along a predetermined path at a desired spacing. For more details of these types of seed placement systems, as well as agricultural planting in general, reference is hereby made to the technical document entitled xe2x80x9cPLANTING FUNDAMENTALS OF MACHINE OPERATIONxe2x80x9d; Breece, Edward H., PhD, et al.; Deere and Co.; 1981, which is incorporated herein by reference.
With a seed metering system including a seed disc as described above, the seed disc typically includes a concentric drive shaft having a sprocket on the outboard end which is driven via a ground drive or the like. The concentrically positioned driven shaft and sprockets may limit the compactness (i.e., reduction in overall size) of the seed metering system.
What is needed in the art is an agricultural seeding machine including a seed metering system which provides positive driving of a seed disc in a more compact manner.
The present invention provides a seeding machine having a seed metering system with a seed disc which is driven in an edge driven manner.
The invention comprises, in one form thereof, a seeding machine including at least one seed metering system and at least one seed placement system. Each seed metering system includes a seed disc having a plurality of spaced apart seed cells and a circumferential edge. An edge drive engages the circumferential edge for rotatably driving the seed disc. Each seed placement system is in communication with a corresponding seed metering system.
The invention comprises, in another form thereof, a method of metering seeds with a seeding machine. A seed metering system includes a seed disc having a plurality of spaced apart seed cells and a circumferential edge, and an edge drive engaging the circumferential edge. The seed disc is rotatably driven using the edge drive. The seeds are received within the seed cells.
An advantage of the present invention is that the seed disc is driven in a manner allowing the seed disc to be placed between the discs of the double disk furrow opener in a more compact manner.
Another advantage is that the circumferential edge of the seed disc can be driven in different ways, including a gear drive, a friction drive, and a ratchet drive.
Yet another advantage is that the relative position of the edge drive to the seed disc (e.g., top or rearward positioned) can be varied depending on the application.